Improvement in piano-fortes



UNITED STATES PATENT OFFICE.

JONAS CIIICKERING, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN PIANO-FORTES.

Specication forming part of Letters Patent No. 3,238, dated September`1, 1848.

To all whom, it may concern.-

Be it known that I, JoNAs CHICKERING, of Boston, in the county ofSuffolk and State of Massachusetts, have invented certain new and usefulImprovements in Certain Parts of Piano-Fortes; and I do hereby declarethat the following description of the same, taken in connection with theaccompanying' drawings thereof, forms a full and exact specification ofmy invention.

Figure l of the drawings above mentioned represents a .top view of aniron frame for a grand7 piano-forte, while Fig. 2 is a longitudinal andvertical section thereof.

In the ordinary method of arranging the strings of a piano-forte theyhave been supported or stretched over the upper surface of a bridge, thehammers striking on the under sides of the wires. Thus at every blow ofone of the hammers upon the string the vibration of the latter wouldcause it t0 rise more or less upon or above the bridge and therebyinjure the tone of the instrument. In order to prevent this evil thestrings were carried through holes of brass pins inserted or screwedinto the frame. This did not wholly accomplish the desired effect, forit was found that the pins would soon become deranged or loose to such adegree as to produce more or less jar or more or less injury to thecorrect action of the strings. To overcome these and other difficulties,I construct the front plate A, Figs. l and 2, inclined or at an anglewith the plane of the frame, and cast upon the lower edge of this frontplate a solid and extended ledge B, which rises above the plate andcontinues from one part of it to the other, as seen in the drawings. Thestrings c o, proceeding from the hitch-pins a a, are passed throughholes bored through the ledge B, and from thence they rise upward towardthe straining-pins b b. The solid ledge through which the strings arecarried by being cast directly upon the plate A is more perfectlysustained by such a union with the plate than if it were attachedthereto by any other means.

Besides, as the whole length of the ledge is presented to counteract anylateral vibration or jar which otherwise might interrupt the harmony ofthe string, the clear tone of the high notes, which heretofore has beenso difficult of attainment and presentation, is completely produced andmaintained.

Another improvement consists in a method of counteracting the greatstrain of the wires and the accidents to the tone, due., liable inconsequence of changes of temperatureviz., by casting` the frame of thegrand piano with long bars d d d, &c., extending from the inclined'front plate and vertical ledge to the curved side plate C. These barsare elevated somewhat above the plane of the springs, and are secured tothe Wooden frame of the instrument at suitable points by screws e e,which pass through them and suitable apertures of the sounding-board,and are then screwed into the wood beneath the sounding-board.

Having thus set forth my improvements, I wish it understood that I amaware that the strings of a piano-forte in their passage from thehitch-pins to the straining-screws have been passed through holes formedthrough a pin screwed or otherwise inserted in a block, and from thesaid pin bent or inclined upward to the straining-screw, and therefore Ido not claim such an arrangement; but

That which I do claim consists in my improvement thereon7 viz:

1. In supporting the strings through asolid ledge cast directly upon thelower part of the inclined iron front plate, through suitable aperturesof which ledge the strings are to be passed in the manner set forth, thetone of the high notes being thereby not only greatly improved butrendered more durable than by the mode first above mentioned.

2. The mode above set forth of counteracting the strain ot' the wires oncertain parts of the iron frame and therebypreventing vibration of suchparts and accidents to the tone; or, in other words, my peculiar methodof constructing the metallic frame of a gra-nd piano-viz., by castingthe same with a series of bars, in combination with an inclined frontplate and vertical ledge and curved side plate, the whole being arrangedas above specified.

In testimony that the above is a correct speciiication of myimprovements, I have hereto set my signature this 14th day of June, ofthe year 1843.

JONAS CIIICKERING. iVitnesses:

R. H. EDDY, JOHN NOBLE.

